Wall construction



y 4, 1964 J. R. WARD, JR 3,140,565

WALL CONSTRUCTION Filed March 13, 1961 2 Sheets-sheet 1 want/011000005 IJOHN ROBERTSON Wa m-JR.

ATTORNEYS July 14, 1964 Y J. RQWARD, JR

WALL CONSTRUCTION 2 Sheets-Sheet 2 Filed March 13, 1961 YINVENTOR. JOHNRoasnrsorv MR0, JR.

.AT TOFPNEYS United States Patent 3,140,565 WALL CONSTRUCTION JohnRobertson Ward, In, Chicago, 111., assignor to Cold Spring GraniteCompany, Cold Spring, Minn., a corporation of Minnesota Filed Mar. 13,1961, Ser. No. 95,263 6 Claims. (Cl. 50-262) This invention relatesgenerally to a wall construction, and more particularly it relates to awall construction wherein generally rectangular panels of substantiallydifferent thicknesses are connected to one another and anchored to astructural supporting unit.

This invention has particular significance in relation to thecurtain-wall type of building construction wherein the wall of thebuilding is supported by the floor support structure, rather than theolder type of construction wherein the floor structure is supported bythe wall of the building. Further, this invention comprehends thecombination of generally rectangular building panels of stone and thelike with other components and panels of other materials, such as glasspanels, the invention including the interconnection of said panels andalso the connection of the panels to the structural supporting unit of abuilding.

An important object of this invention is the provision of a wallconstruction in which the attachment and connection of the wall panelsto one another and the anchoring of the same to a building supportpermits attachment of the panels at any desired location, and alsoeliminates shelf angles and other commonly used miscellaneous supportingsteel.

Another object of this invention is the provision of a wall constructionin which the attachment and connection of the wall panels to a buildingsupport is designed so as to utilize the strength of the stone buildingpanels for the support thereof.

Another object of this invention is the provision of a novel wallconstruction in which the attachment and connection of the wall panelsto a building support is characterized by fast erection of the panelsand installation thereof in a rapid sequence whereby to reduce to aminimum the intermittent idle periods in the operation of erectionmachinery.

A still further object of this invention is the provision of a wallconstruction in which the attachment and connection of the wall panelsto one another and also to a building support is designed so as topermit flexiblity in erection sequence, and also to permit subsequentreplacement of individual panels.

In the handling of stone panels of small thickness relative to thelength and width thereof during transportation and installation thereofin a wall structure, fracture of a panel sometimes occurs at the edge orcorner portions thereof, as well as transversely or longitudinallythrough the panels intermediate the sides or ends thereof. Such fractureof a stone panel during the handling thereof, or during its use as partof the building wall, is not only hazardous to the workmen orbystanders, but also involves a substantial replacement expense. Animportant object of my invention is, therefore, the provision of novelmeans for reinforcing a stone building panel to minimize the occurrenceof cracking or fracture thereof. To this end, I provide a generallyrectangular slab-like stone panel having an outwardly opening groove orchannel around the periphery thereof, and an elongated metallicreinforcing element tightly encompassing said slab Within said grooveand locked therein.

A further object of this invention is the provision of a wallconstruction in which the attachment and connec tion of building panelsof substantially differing transverse dimensions is designed so as toprovide maximum edge protection of the panels, to provide positivesealing and seating between the panels, and yet provide for theallowance of structural and thermal movement therebetween.

A further object of this invention is the provision of a wallconstruction in which the attachment and connection of wall panels ofsubstantially differing transverse dimension greatly reduces the numberof joints heretofore used in joining the panels of lesser transversedimension to one another.

A still further object of this invention is the provision of weepagecollecting means adjacent the rear faces of the panels so as to providefor the collection and drainage of any condensation forming on the rearface of the panels.

Other objects of this invention reside in the provision of a wallconstruction which eliminates expensive framing, is characterized by lowmaintenance costs, is durable and strong in construction, and highlyeffective in the vindication of its purposes.

The foregoing and other objects and advantages of this invention willbecome apparent from the following detailed specification, appendedclaims and attached drawmgs.

Referring to the drawings wherein like reference characters indicatelike parts or elements throughout the several views:

FIG. 1 is a view in elevation of my wall construction, some parts beingbroken away;

FIG. 2 is a view in perspective of one of the stone building panels usedin the wall construction, and showing the anchoring brackets used indirectly attaching the stone building panels to the structuralsupporting unit of a building;

FIG. 3 is an enlarged view in vertical section taken on the line 33 ofFIG. 1;

FIG. 4 is an enlarged view in vertical section taken on the line 44 ofFIG. 1;

FIG. 5 is an enlarged view in horizontal section taken on the line 55 ofFIG. 1, some parts being broken away;

FIG. 6 is an enlarged view in horizontal section taken on the line 66 ofFIG. 1;

FIG. 7 is an enlarged View in horizontal section taken on the line 7-7of FIG. 1; and

FIG. 8 is an enlarged View in transverse section of one element of myinvention.

Referring to the drawings, and particularly FIG. 1 thereof, a wallconstruction is shown which comprises stone building panels, representedin general by the reference numeral 1, and glass secondary panels,represented in general by the reference numeral 2. It should beunderstood that the stone building panels 1 may be formed of anysuitable stone building material or simulated stone building material,such as granite or concrete. It should also be understood that the glasssecondary panels 2 are preferably formed to be of substantially lesstransverse dimension or thickness than the transverse dimension orthickness of the stone building panels 1, the secondary panels 2 beingformed from any material which may be architecturally suitably combinedwith the stone building panels 1. Examples of suitable secondary panels2 would be plate glass, colored glass, tempered glass, translucentpanels, double-wall glass, aluminum, bronze, stainless steel, operablesash, solar shades, and louvers. The secondary panel shown is comprisedof inner and outer glass panes secured together at their perimeters by aconventional sealout. As seen in FIG. 3, the reference letter Arepresents a structural supporting unit, such as a concrete floorstructure commonly used in curtain-wall constructions.

Referring now to FIG. 2, the stone building panel 1 defines a front face3, a rear face 4, side edges 5, a top edge 6, and a bottom edge 7. Thestone building panel 1 also defines at both side edges 5 thereof twovertically spaced pairs of cross-sectionally rearwardly converginggrooves or slots 8, which extend in general parallelism generallyhorizontally inwardly from the side edges of the stone building panel 1and which open rearwardly at the rear face 4 of said stone panel 1.

For the purpose of directly attaching the stone building panels 1 to thestructural supporting unit A, a pair of anchoring devices are provided,the anchoring devices being shown in FIGS. 2 and 3 and represented ingeneral by the reference numeral 9. The anchoring devices 9 are one eachassociated with each two pair of slots 8 at both side edges 5 of thestone panel 1. The anchoring devices 9 each comprise an elongatedgenerally vertically disposed strut 10 and a pair of elongatedvertically spaced generally parallel and generally horizontally disposedchannel members 11. The channel members 11 are rigidly secured, as bywelding, in general perpendicularity to the strut 10 adjacent theopposite ends 12 thereof. Each of the channel members 11 is formed todefine flange portions 13 which diverge outwardly from the web portion14 thereof. It should be obvious that before the channel members 11 aresecured to the strut 10, the vertical spacing thereof is adjusted toconform to the vertical spacing between the pairs of grooves 8 whichhave been cut in the opposite side edges 5 of the stone panel 1.

Referring to FIGS. 2 and 3, it is shown that each of the channel members11 are adapted to have their flange portions 13 slidably received withina corresponding pair of grooves 8, said channel members 11 beingslidably inserted from the side edges 5 of the front panel 1 so as todispose said flange portions 13 within the grooves 8 in theabove-described manner. FIG. 3 illustrates one method of securing theanchoring devices 9 to the structural supporting unit A; however, itshould be obvious that any suitable means for affecting the attachmentmight be suitably employed. As shown, a pair of angle brackets 15 areone each secured to the opposite ends 12 of each of the anchoringdevices 9 by means of cap screws 16. Also, the structural supportingunit A is formed to define vertically opening recesses a spaced adjacentthe outer edge b of the structural supporting unit A. Such aconstruction permits the attachment of the anchoring devices 9 to thestructural supporting Unit A by means of the connection of the anglebrackets 15 adjacent the recesses a, the angle brackets being secured bybolts 17.

In the light of my novel means for anchoring the stone panels 1 to thestructural supporting unit of a building, no necessity further existsfor utilizing one stone panel to support another, as has been commonpractice heretofore in the outer walls of building structures. Hence, inmy arrangement, the stone panels 1 may be of considerably less thicknessbetween the front and rear faces 3 and 4 than formerly. The use of arelatively thin stone panel does, however, present problems intransportation, handling and in use, inasmuch as the relatively thinpanels are more susceptible to fracture from shock, particularly at thecorners or edge portions thereof, than are relatively thick stoneblocks. Therefore, I have devised means for increasing the compressivestrength and impact resistance of the stone panel 1 whereby to greatlyaid in the prevention of fracturing of the stone panel 1, particularlyat the edge and corner portions thereof. The stone panel 1 defines atthe edges 5-7 thereof a marginal annular laterally outwardly openinggroove, which groove is represented at both side edges 5 of the stonepanel 1 by the reference numeral 18 and is represented at the top andbottom edges 6, 7 thereof by the reference numerals 19 and 19arespectively. A marginal tension band 20 is received within the marginalgroove 19, 19, 19a and is rigidly secured about the stone panel 1, as bywelding, riveting, clipping or any other suitable manner. The tensionband 20 may be formed from steel or any other suitable material and isintegrally locked around the entire permieter of the stone panel 1 so asto enhance the fiexural strength and impact resistance thereof byprestressing the panel 1 with band 20. If, during use, fracture shouldoccur in the stone panel 1, the band 20 positively holds the paneltogether to prevent severed portions thereof from displacement, thusavoiding possible injury to persons who might be in the immediatevicinity. It should be noted that the marginal tension band 20 is offurther functional importance in that after the channel members 11 ofthe anchoring devices 9 have been received within the grooves 8 of thestone panel 1, the tension band 20 prevents endwise slippage of theanchoring devices 9 from the panel 1 since the tension band 20 overliesthe ends of the channel members 11 of the anchoring devices 9. Aparticular advantage of the direct atachment of panel 1, hereinbeforedescribed, in combination with the safety feature and other advantagesof the band 20 allows the use of stone panels 1 in direct cantileveraction to resist loads perpendicular to panels 1, such as wind or otherforces. This forms an important part and function in the use of stone,such as panels 1, as a more entire structural element and provides foreffective, less expensive stone construction.

A further derivative advantage of the above-described means forattaching the stone panels 1 directly to the structural supporting unitA by means of the anchoring devices 9 is that the arrangement permitsthe secondary panels 2, preferably formed from a material such as glass,to be directly glazed to the edge of the stone panels 1 without thenecessity of the use of intermediate metal lintels and frames such ashave been heretofore used in connection with previous types ofattachment means for stone panels. Since the coeflicients of expansionof stone (such as granite) and glass are approximately equal, the glasssecondary panels 2 may be directly glazed to the stone panels 1, asshown in FIG. 3. The direct glazing of the glass panels 2 to the stonepanels 1, without the use of intermediate metallic glazing frames, aswas heretofore common, virtually eliminates any separation between thejoints of the stone panels 1 and the secondary panels 2 whereby toeliminate the need for frequent resealing of the joints, which frequentrescaling has been heretofore necessary in light of the greatly varyingdifference between the coefficients of expansion of the interveningmetallic frames and the stone glass panels. Referring particularly toFIGS. 3, 4, and 6, it will be seen that each of the glass secondarypanels 2 comprises spaced parallel panes 2a and 2b and a marginalspacing member 22. The panes and marginal spacing member are sealedtogether in a well-known manner, not comprising the instant invention,the panels 2 in their entireties being commercially available from glassmanufacturers. Each of the glass panels 2 is provided with across-sectionally generally U-shaped peripheral sealing member 21 whichreceives the marginal edge of the glass secondary panel 2. Theperipheral sealing member 21 is preferably formed from a material suchas cellular neoprene, said sealing member 21 being shown in crosssection in FIG. 8. The sealing member 21 may be applied to the glasspanel 2 before the same is shipped to the erection job site so as toprovide edge and fracture protection for the glass panel 2 duringtransit. As seen in FIG. 3, the glass panel 2 is sealed by means ofsealant 23 within the annular groove 18, 19, 19a of the stone panel 1.The sealant 23 may be of any suitable sealing material such as apolysulfide sealant. It will be further noted that the marginal grooveportion 19a of the stone panel 1, is of substantially greater depth thanthe opposite groove portion 19. With this arrangement, when one of thepanels 1 is mounted above another, as shown in FIGS. 1 and 3, with asecondary glass panel 2 therebetween, removal of a secondary panel 2 andreplacement thereof may be easily effected. It is only necessary thatthe panel 2 be raised into the groove portion 19a a distance to enablethe lower edge of the panel 2 to clear the underlying groove portion 19,and the panel 2 then swung outwardly until the lower edge thereof clearsthe front surface 3 of the underlying stone panel 1, after which thepanel 2 is lowered until the upper edge thereof is clear of theoverlying groove portion 19a. The thickness and compressibility of theperipheral sealing member 21 permits such removal of the secondarypanels 2, and a replacement panel is slipset into position in the revrsemanner, and sealed in place.

In some applications for ease of installation of panels 1, it may bemore desirable to have the upper marginal grove portion the one ofgreater depth rather than the lower grove portion; and it should beclear that my invention encompasses this construction also, that is,upper groove portion 19 is of substantially greater depth than theopposite groove portion 19a and to an extent sufficient to readilyinsert panel 1 between two secondary panels 2 or the like, when thelatter are in their fixed positions. A further function of the largergroove portion, either 19 at the top or 19a at the bottom, is that itprovides a space for relative vertical movement or deflection betweenadjacent panels in the nature of an expansion joint between elements ofthe wall system.

FIG. 5 discloses the joint construction between the adjoining stonebuilding panels 1. It is noted that the grooves 18 defined at the sideedges 5 of each of the stone panels 1 are extended inwardly at bothsides thereof so as to define vertically extending channels 24. When thestone panels 1 are fitted into their final position, the channels 24receive inner and outer vertically disposed mullion bars 25 which arespaced adjacent the side edges of the tension band 20. The mullion bars25 are sealed within the channels 24 by means of a suitable sealant 23.

FIG. 6 discloses the form of the joints between adjoining glasssecondary panels 2. As shown, the secondary panels 2 are disposed inend-to-end relationship with the annular sealing member 21 of eachthereof abutted against one another. Also, each of said joints isprovided with inner and outer cross-sectionally generally T- shapedstiffener bars 26, which are disposed against the opposite sides ofabutted annular sealing members 21, as seen particularly in FIG. 6. Itis noted that the stiffener bars 26 are held in the above describedposition adjacent the joint between the adjoining glass panels 2 by thereception of longitudinally extended fiat end portions 26a of thestiffener bars 26 within recesses 27 defined intermediate the rnullionbars 25 and the tension band 20. Also, the joint is then finished withthe usual application of the sealant 23. FIG. 4 is helpful in showingboth of the abovedescribed joints in vertical section. Preferably, thestiffener bars 26 are of a length equal to the height of the secondarypanels 2, so that the stiffener bars 26 at the front side of the panels2 may be removed in the same manner as above described in connectionwith the secondary panels 2, to permit a damaged or broken panel 2 to beremoved and a new panel 2 slipset into place.

Referring again to FIGS. 2 and 3 means is provided adjacent the bottomedge 7 of the stone panel 1 for the collection of any condensation thatmight form on the rear face 4 of the stone panel 1. Therefore, and inaccordance with my invention, a horizontally extending groove 28 is cutadjacent the bottom edge 7 of the stone panel 1 at an oblique angle tothe plane of the rear face 4 thereof, and is adapted to receive a fiangeportion of an elongated cross-sectionally generally Z-shaped weepagechannel member 29. The weepage member 29 defines a generallyintermediately spaced aperture 3%) which communicates With a passageway31 leading to the front portion 3 of the stone building panel 1 so as tocollect any condensation forming on the rear face 4 of the panel 1 andpermit flow and drainage thereof to the outside of the wall of thebuilding. It should be noted that FIG. 7 discloses the jointconstruction for a bottom row of stone panels 1a, wherein the same isformed by the use of an elongated spacing strip 32 and the applicationof a sealant 23.

Having specifically described my invention, the fabrication andinstallation thereof is thought to be readily understandable; however,it might be helpful to briefly state that after the stone panels 1 areformed to the shape shown in FIG. 2, including the cutting of thegrooves 8, 24, 28, the anchoring devices 9 are inserted from the sideedges 5 of the stone panels 1. At this time the same are ready to betransported to the building job site. It should also be noted that theannular sealing members 21 are installed on the secondary glass panels 2before shipment thereof to the building job-site. Field erection of thewall construction thereafter merely comprises horizontal adjustment (ifnecessary) of the anchoring devices 9 on the panels, and subsequentattachment of the stone and glass panels 1, 2 in the above describedmanner. It should be noted that the angle brackets 15 may be verticallyadjusted with respect to the structural supporting unit A by the use ofsuitable shims 33.

This invention has been thoroughly tested and found to be completelysatisfactory for the accomplishment of the above objects; and while Ihave shown a preferred embodiment thereof, I wish it to be specificallyunderstood that the same may be modified without departure from thescope and spirit of the appended claims.

What I claim is:

1. In a wall construction for mounting on a frame structure, a generallyrectangular stone panel having a front face and rear face and havingopposed side edges and top and bottom edges, said rear face of saidstone panel intermediate said top and bottom edges thereof having pairsof rearwardly opening grooves therein, each pair of said groovesextending generally horizontally inwardly from a different one of theopposite side edges of the panel, the grooves of each pair thereofdiverging forwardly from said rear face toward said front face of thepanel, and a pair of anchoring devices for attaching said panel to saidframe structure, said anchoring devices each comprising a base memberand a pair of vertically spaced generally horizontally extendingforwardly diverging flanges secured to said base member and slidablyreceived in one respective forwardly diverging groove of a cooperatingpair of said grooves longitudinally inwardly from the adjacent side edgeof said panel, and bracket elements on said base members for mountingsaid base members to said frame structure.

2. In a wall construction, a structural supporting unit, a generallyrectangular stone building panel having front and rear faces and havingside edges and top and bottom edges, said stone building panel definingat both side edges thereof two vertically spaced pairs ofcross-sectionally forwardly diverging grooves which extend in generalparallelism generally horizontally inwardly from said side edges of saidpanel and which open rearwardly at the rear face of said panel, and apair of anchoring devices one each associated with said grooves at eachof said side edges of said panel for directly attaching said panel tosaid structural supporting unit, said anchoring devices each comprisingan elongated generally vertically disposed strut, and a pair ofelongated vertically spaced generally horizontally extending generallyparallel channel members rigidly secured in general perpendicularity tosaid strut, said channel members having web portions engaging said strutand flange portions which diverge outwardly from the Web portionsthereof, said channel members each having their flange portions slidablyinserted into a corresponding pair of said grooves laterally inwardlyfrom the side edges of said panel so as to dispose said flange portionswithin said grooves, said struts being readily securable to saidstructural supporting unit so as to attach said panel thereto.

3. In a wall construction, a structural supporting unit, a generallyrectangular stone building panel having front and rear faces and havingside edges and top and botttom edges, said stone building panel definingat both side edges thereof two vertically spaced pairs ofcross-sectionally forwardly diverging grooves which extend in generalparallelism generally horizontally inwardly from said side edges of saidpanel and which open rearwardly at the rear face of said panel, saidpanel also defining at the edges thereof a marginal laterally outwardlyopening groove, a pair of anchoring devices one each associated withsaid diverging grooves at each of said side edges of said panel fordirectly attaching said panel to said structural supporting unit, saidanchoring devices each comprising an elongated generally verticallydisposed strut, and a pair of elongated vertically spaced generallyhorizontally extending generally parallel channel members rigidlysecured in general perpendicularity to said strut, said channel membershaving generally vertical web portions and spaced flange portions whichdiverge outwardly from the web portion thereof, said channel memberseach having their flange portions slidably inserted into a correspondingpair of said diverging grooves laterally inwardly from the side edges ofsaid panel so as to dispose said flange portions within said grooves,said struts being readily securable to said structural supporting unitso as to attach said panel thereto, and an elongated marginalreinforcing element received within said marginal groove and rigidlysecured about said panel.

4. In a wall construction, a structural supporting unit, a generallyrectangular stone building panel having front and rear faces and havingside edges and top and bottom edges, said panel having pairs ofrearwardly opening diverging grooves in the rear face intermediate saidtop and bottom edges of said panel, each pair of said grooves extendinggenerally horizontally inwardly from a different one of the oppositeside edges of the panel, a pair of anchoring devices, each anchoringdevice having a pair of diverging fian es received within an associatedpair of said grooves directly attaching said panel to said structuralsupporting unit said stone building panel defining at the edges thereofa marginal laterally outwardly opening groove which communicates withsaid grooves in said panel, a marginal reinforcing band received Withinsaid marginal groove and rigidly secured about said panel holding saidanchoring devices within their said associated grooves, a generallyrectangular secondary panel of less transverse dimension than thetransverse dimension of said marginal groove about said stone buildingpanel, and an annular sealing member received about the marginal edge ofsaid secondary panel, said secondary panel with said sealing memberbeing received within said marginal groove adjacent one edge of saidstone building panel whereby to seat said secondary panel Within themarginal groove of said stone building panel.

5. In a wall construction, a structural supporting unit, a generallyrectangular stone building panel having front and rear faces and havingside edges and top and bottom edges, said stone building panel definingat both side edges thereof two vertically spaced pairs ofcross-sectionally forwardly diverging grooves which extend in generalparallelism generally horizontally inwardly from said side edges of saidpanel and which open rearwardly at the rear face of said panel, saidpanel also defining at the edges thereof a marginal laterally outwardlyopening groove, a pair of anchoring devices one each associated withsaid diverging grooves at each of said side edges of said panel fordirectly attaching said panel to said structural supporting unit, saidanchoring devices each comprising an elongated generally verticallydisposed strut, and a pair of elongated vertically spaced generallyhorizontally extending generally parallel channel members rigidlysecured in general perpendicularity to said strut, said channel membershaving generally vertical web portions and spaced flange portions whichdiverge outwardly from the web portion thereof, said channel memberseach having their flange portions slidably inserted into a correspondingpair of said diverging grooves laterally inwardly from the side edges ofsaid panel so as to dispose said flange portions within said grooves,said struts being readily securable to said structural supporting unitso as to attach said panel thereto, and an elongated marginalreinforcing element received within said marginal groove and rigidlysecured about said panel, said stone building panel further havingcollecting means disposed adjacent the bottom edge of the rear face ofsaid stone building panel and having a passageway communicating withsaid collecting means and leading to the front portion of said stonebuilding panel whereby to provide for the collection and disposal of anycondensation forming on the rear face of said panel.

6. The structure defined in claim 5 in which said stone panel is formedto provide a horizontally extended groove in its rear face above saidpassageway, said channel sloping forwardly and downwardly from said rearface, and in which said collecting means further comprises an elongatedchannel member having a flange portion received in said groove and alsohaving an aperture which communicates with said passageway.

References Cited in the file of this patent UNITED STATES PATENTS1,041,990 Freund Oct. 22, 1912 1,195,643 Baumgartl Aug. 22, 19162,277,984 Jenkins Mar. 31, 1942 2,315,956 Heath Apr. 6, 1943 2,351,856Henderson June 20, 1944 2,748,592 Kelly June 5, 1956 2,895,182 EvansJuly 21, 1959 2,944,641 Peterson July 12, 1960 OTHER REFERENCESPrefabrication, March 1957, pages 22l225. German printed application3,865, Mar. 29, 1956.

1. IN A WALL CONSTRUCTION FOR MOUNTING ON A FRAME STRUCTURE, A GENERALLYRECTANGULAR STONE PANEL HAVING A FRONT FACE AND REAR FACE AND HAVINGOPPOSED SIDE EDGES AND TOP AND BOTTOM EDGES, SAID REAR FACE OF SAIDSTONE PANEL INTERMEDIATE SAID TOP AND BOTTOM EDGES THEREOF HAVING PAIRSOF REARWARDLY OPENING GROOVES THEREIN, EACH PAIR OF SAID GROOVESEXTENDING GENERALLY HORIZONTALLY INWARDLY FROM A DIFFERENT ONE OF THEOPPOSITE SIDE EDGES OF THE PANEL, THE GROOVES OF EACH PAIR THEREOFDIVERGING FORWARDLY FROM SAID REAR FACE TOWARD SAID FRONT FACE OF THEPANEL, AND A PAIR OF ANCHORING DEVICES FOR ATTACHING SAID PANEL TO SAIDFRAME STRUCTURE, SAID ANCHORING DEVICES EACH COMPRISING A BASE MEMBERAND A PAIR OF VERTICALLY SPACED GENERALLY HORIZONTALLY EXTENDINGFORWARDLY DIVERGING FLANGES SECURED TO SAID BASE MEMBER AND SLIDABLYRECEIVED IN ONE RESPECTIVE FORWARDLY DIVERGING GROOVE OF A COOPERATINGPAIR OF SAID GROOVES LONGITUDINALLY INWARDLY FROM THE ADJACENT SIDE EDGEOF SAID PANEL, AND BRACKET